Generic name: entacapone [ en-TAK-a-pone ]
Brand name: Comtan
Dosage form: oral tablet (200 mg)
Drug class: Dopaminergic antiparkinsonism agents

Medically reviewed by Drugs.com on Oct 16, 2024. Written by Cerner Multum.

What is entacapone?

When used with carbidopa and levodopa (Atamet, Parcopa, Sinemet), entacapone increases levels of levodopa in the body.

Entacapone is used together with carbidopa and levodopa to treat "wearing-off" symptoms of Parkinson's disease, such as stiffness, tremors, muscle spasms, and poor muscle control.

Entacapone may also be used for purposes not listed in this medication guide.

Entacapone side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Entacapone may cause serious side effects. Call your doctor at once if you have:

• agitation, confusion, unusual thoughts or behavior;

• hallucinations (hearing or seeing something that is not there);

• very stiff (rigid) muscles, high fever, sweating, fast or uneven heartbeats, tremors, feeling like you might pass out;

• severe or ongoing diarrhea;

• restless muscle movements in your eyes, tongue, jaw, or neck (or worsening of Parkinson symptoms); or

• unexplained muscle pain, tenderness, or weakness especially if you also have fever, unusual tiredness, and dark colored urine.

You may notice that your urine appears orange, red, brown, or black in color. This is not a harmful side effect unless you also have muscle pain and unusual weakness.

Common side effects of entacapone may include:

• dizziness, drowsiness;

• nausea, vomiting, stomach pain;

• diarrhea;

• dry mouth; or

• uncontrolled muscle movements.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Related/similar drugs

Warnings

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Before taking this medicine

You should not use entacapone if you are allergic to it.

To make sure entacapone is safe for you, tell your doctor if you have:

• low blood pressure;

• liver disease; or

• a history of mental illness or psychosis.

You may have increased sexual urges, unusual urges to gamble, or other intense urges while taking entacapone. Talk with your doctor if this occurs.

People with Parkinson's disease may have a higher risk of skin cancer (melanoma). Talk to your doctor about this risk and what skin symptoms to watch for. You may need to have regular skin exams.

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It is not known whether entacapone passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

How should I take entacapone?

Follow all directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Entacapone must be taken together with carbidopa and levodopa. Entacapone used alone will not treat symptoms of Parkinson's disease.

Entacapone can be taken with or without food. Taking the medicine with food may help prevent nausea, which is a common side effect of entacapone.

Drink plenty of liquids while you are taking entacapone.

Entacapone may cause you to fall asleep during normal daytime activities such as working, talking, eating, or driving. You may fall asleep suddenly, even after feeling alert. Tell your doctor if you have any problems with daytime sleepiness or drowsiness.

Call your doctor if you have ongoing vomiting or diarrhea, or if you are sweating more than usual. You can easily become dehydrated while taking this medicine, which can lead to severely low blood pressure or a serious electrolyte imbalance.

You should not stop using entacapone suddenly. Follow your doctor's instructions about tapering your dose.

Store at room temperature away from moisture and heat.

Entacapone dosing information

Usual Adult Dose for Parkinson's Disease:

200 mg orally concomitantly with each dose of levodopa-carbidopa up to a maximum of 8 times a day
Maximum dose: 1600 mg per day

Comments:
-Upon initiation, a majority of patients required levodopa dose reductions or an extension of the interval between their levodopa doses, especially those receiving levodopa doses of 800 mg/day or greater, and patients with baseline moderate or severe dyskinesia.

Use: As an adjunct to levodopa-carbidopa to treat end-of-dose "wearing-off" in patients with Parkinson's disease.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include agitation and aggression, or severe drowsiness, confusion, and loss of consciousness.

What should I avoid while taking entacapone?

This medication may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert. Entacapone may cause you to fall asleep suddenly, even after feeling alert.

Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall.

Avoid drinking alcohol. It can increase some of the side effects of entacapone.

What other drugs will affect entacapone?

Taking entacapone with other drugs that make you sleepy can worsen this effect. Ask your doctor before taking entacapone with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety, depression, or seizures.

Tell your doctor about all medicines you use, and those you start or stop using during your treatment with entacapone, especially:

• isocarboxazid;

• linezolid;

• methylene blue injection;

• phenelzine; or

• tranylcypromine.

This list is not complete. Other drugs may interact with entacapone, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

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